Automatic telephone system



s. SIMONETTA AND-A. ROSA.

AUTOMATIC TELEPHONE SYSTEM. APPLICATION FILED MAN. 4. 1918.

1,390,729. v PatentedSept. 13, 1921.

3 $HEETS-SHEET l.

gln'ventors:

G. SIMONETTA AND A. ROSA.

AUTOMATICTELEPHO'NE SYSTEM. APPLICATION FILED MAR-4,1918.

1,390,729. Patented Sept. 13, 1921.

3 SHEETS-SHEET 2.

Si n

G. SIMONETTA AND A. ROSA.

AUTOMATIC TELEPHONE SYSTEM. APPLICATION FILED MAR-4, 1913.

3 SHEETS-SHEET 3.

Inventors:

" i. h. Paw

Attomevn PatentedSept. 13, 1921.

UNITED STATES PATENT OFFICE.

GIUSEPT'E BIMONETTA AND AUGUST!) ROSA, OF MILAN, ITALY.

AUTOMATIC TELEPHONE SYSTEM.

Application filed March 4,

To all whom itmoy concern:

Be it known that we, GIUSEPPE SIMONETTA and AUcUs'ro RosA, both subjectsof the King of Italy, residing at 4 Via Dante, Milan, in the Kingdom ofItaly, have invented new and useful Improvements in Automatic TelephoneSystems, (for which we have filed application in Italy November 20,1916, Patent No. 156,926,) of which the following is a specification.

The present invention relates to an improved system of automatictelephony in which the current sent into the line wire by the callingsubscriber causes a free trunk line to select, by means of a searcher ofthe calling line, called hereinafter linesearcher, one of the contactgroups on which the calling line is multipled and therewithshort-circuits a registrating device called hereinafter registrator andprevents any other trunk line controlled by the same registrator fromcoming into operation, all this being performed through the callingsubscriber taking oif his receiver from the hook of the apparatus. Theformation of the first figure of the number called up has the followingeffects: The registrator is set into motion, a selector or trunk linesearcher corresponding to the si aled figure is picked outand set intomotion, a pointer of the selector is stopped in a determined positioncorresponding to the calling line, owing to which position the callingline is connected to a free trunk line leading either to a secondselector or to a connector according to whether the exchange is adaptedto accommodate 10,000 or 1000 lines. The

registrator already mentioned is disconnected and a further registratorinserted which is intended either to act upon the eventual secondselector in a similar manner to that of the first registrator in respectto the first selector, or to pick out in the connector a pointcorresponding to the number called up and to connect up the trunk line(which at this moment is served by the registrator in question and isconnected to the calling apparatus) with the apparatus called for. Thesystem further comprises a set of magnets for each trunk line of theconnector, these magnets being intended to maintain the connection withthe line called for if the latter is free, or to break the saidconnection if the called for line is not free, and the secondregistrator being liberated Specification of Letters Patent. PatentedSept. 13, 1921.

1918. Serial No. 220,399.

and left available for other calls as soon the connection has beenestablished.

The invention also refers to a type of linesearcher differing from thoseused heretofore in that each rotating pointer of a num. ber rotatable onthe searcher spindle corresponds to a trunk line and can be stopped onit and so establish the connection without interfering with the furthermotion of the searcher spindle and of the other pointers which remainavailable for other calling subscribers in such a way that two pointerscannot be stopped in correspondence to the same calling line at a time.The new linesearcher accordingly works as many ordinary searchers as thepointers with which it is fitted can comprise a considerable number ofsubscribers, and yet its construction remains quite simple.

The invention further refers to selectors and connectors, which are meremodifications of the line-searchers in relation to the use for whichthey are intended and which will be hereinafter disclosed. 7

Hence a great simplicity in the plant and a reat certainty of working isattained.

he invention isillustrated by way of example in the annexed drawings:

Figures 1 and 2 conjointly show the general scheme of the partsdescribed and of their connections.

Figs. 3 and 4 are a vertical section and a plan respectively of aline-searcher.

The line-searcher according to this invention, as represented in Figs. 3and 4, is adapted for quite a large number of lines and consists of astationary portion A corresponding to the multiple of the manual system,and of a revolving portion corresponding to the set of plugs in themanual system and consisting of a set of pointers.

The stationary portion comprises a cylinder on Whose generating linesare multipled the subscriber lines in the case of the devices working ascalling-line-searchers or as connectors, or the trunk lines from theprevious devices in the case of the devices working as selectors. Inaddition thereto each device comprises a ring-shaped collector providedwith contacts C the auxiliary magnets spoken of hereinbelow beingenergized across this collector.

The revolving portion comprises a spindle --d,,- whose rotation isstarted at the beginning ef the call,- 111 this case the spindle andtherewith. the calling must be provided with a clutch; in the drawing amagnetic clutch is shown consisting of a set of magnets e.., in front ofwhich slides a soft iron disk -f sufficiently thin to allow of itsslightly deflecting under the action of the electro-magnets; the diskf., is driven by a motor-and revolves con tinuously; in order to set thespindle c6 revolvingit is obviously suincient to excite the magnets eThe clutch might however be of any other type whatever or be dispensedwith altogether if the motor can be stopped.

On the spindle -cZ5 a plurality of pointers 9 are fitted, the same beingsuitably spaced acrossthe spindle length and equal in number to thetrunk lines that are placed at the disposal of. every hundredsubscribers. These pointers are loose on the spindle and can be madefast with it by expansions h ;-"set at equal angles around the spindle,sothat, when running; the pointers are spaced apart by equal angles. In

their rotation the pointers pass in front of the polar expansions of aset of electromagnets not shown in the drawing, or theythemselves'arecarrying 'electromagnets moving in front of a soft iron plate as shownin the drawing. In both cases the pointer can'be displaced from itsposition, its arm g., pivotingjabout the pin Z fixed on the spindlesleeve. By this swinging the pointer is released from the expansion [twhich influenced it. andithen rests upon the springs facing 'it'and'i'n-this way connects a trunk line to the line corresponding to thecylinder generating line in frontof which it has been stopped. f r

The action of the magnets i., is determined by a set-of brushes mrubbing the contacts of the ring collector.

To each brush there corresponds a pointer and consequently a trunk line.The brushes -m.,- are fitted at the outer ends of the radial arms n.,which are secured to a central hub that partakes of the continuousrotationofthe spindle -cZ and are so arranged that when one brushreaches the contact corresponding to a determined trunk line, thecorresponding pointer faces that same line.

When a pointer has been brought to a stop line has been connectedthrough with a tree trunk line and with the called for line, no furtherpointer can be stopped by the same calling line, and

the spindle with the remaining pointers corresponding to tree lines can"revolve on and effect the connection of another calling line withanother tree trunk line. Besides, the arrangement is such that a pointercan not be attracted unless it be in contact with the expansion h viz.just in correspondence to its own arm n the object of this arrangementbeing to prevent the pointer being attracted when it is not exactlyopposite the cylinder generating line corresponding to the position oil.its own arm n., at that same moment.

The operation otthis device is described as applied to the calling-linesearcher. The device works just the same when applied to the selectors(or trunks searchers) or to the connectors.

When a subscriber calls up the collector contact corresponding to theline of the calling subscriber is energized, in the manner hereinafterexplained. As the spindle rotates the first brush passing over thecontact and corresponding to a tree line. and therefore rotating itspointer along with it, transmits a current to the stopping magnet -21,-across the said pointer and its expansion Accordingly the pointer istilted and rests upon the springs it fa es at that moment, these springsbeing just those corresponding to the calling line. In this way thepointer makes the connection between the line coming from the callingsubscriber and the trunk line corresponding to the pointer.

The selector and connector work in substantially the same manner. ()tcourse the details may be varied from those described and illustrated inthe drawing without dcparting from the spirit and scope oi theinvention. In particular the spring contacts in the stationary portionmight be repla ed by rubbing contacts, the pointers being then fittedwith brushes that slide over the contacts and swinging on the loosecentral. sleeve only partially. The position and form of the collectoncontacts and brush star might also be varied.

By means of the line-searchers, selectors and connectors (these beingsuitably connected with trunk lines and the latter being fitted withregistering devices or registrators that are released antomatically assoon as the connection is established) the calling line is connected upto the called one.

a In a general way the system is arranged nal, the pointer is disengagedfrom its expansion -7i and stops thus connectln'g the calling line andthe trunk line. Simultaneously the calling line is connected up to a.

tree trunk line device registering the first figure of the number calledup.

The trunk line thus engaged is connected in shunt to all the selectorsof the first set in the group to which the calling telephone belongs.The object of the first registrator is tofcause the first figure toremain vir-' tually formed a convenient lapse of time and to set thecorresponding first selector int0 rotation, and to stop it as soon as apointer of the said first selector comes opposite the line is signaled.

Now the calling subscriber is connected to a last trunk line and to aregistrator whose object is to maintain the signaling of the two lastfigures of the number. When this signaling is completed, the connectorbelonging to the hundred to which the called up subscriber appertainsstarts revolving. The last trunk lines lead to the connector pointersand, when the revolving pointer connected to the calling line comesopposite the called up line (who is multipled on the contacts of one ofthe generating lines of the connector) if the called telephone is freethat pointer is brought to a stillstand and connects the callers line tothat of the called subscriber. The registrator is then at once releasedand the calling signal sent into the called line. When the called upsubscriber lifts his receiver from the hook, he is con nected up to thecalling line across the speaking line. If the called telephone isengaged, the pointer is not brought to a stillstand and all parts whichhad been engaged during the call are now released excepting the set ofmagnets of the calling subscriber which remain engaged and, whilepreventing others calling him up, send the engaged signal into thecalling line.

At the end of the conversation, as soon as i one of the users hangs uphis receiver, all

the parts that were locked during the conversation are released with theexception of the magnets of the subscriber that has not yet hung up hisapparatus, who received a signal, for instance the same engaged signal,that advises him of the end of the conversation.

As may be seen, all parts are so arranged that they remain locked onlyaslong as they are working and are set ree immediately their action isover.

With reference to Figs. 1 and 2, A is the Batt 29--2S-cc80-31-T,,

the magnet ccomes into action and ,7

calling, B- the called subscriber, C- the line-searcher, --D- the firstregistrator, -E- the selector, Grthe connector, --M N the magnets of thesingle subscriber-lines for controlling the line-searchers.

UaZL- lhe calling subscriber lifting his receiver from the hook,disconnects the ringing apparatus, closes the contact 2 and establishesthe circuit T,--l-2-3 l-a-Batt- T,, where and hereinafter Battindicatesthe battery and T- the grounds.

The magnet -a attracts its armature fitted with multiple contacts andcloses the contacts 6-l7--9. By closing the contact 6 the callers fourthwire leading to the caller's connector is earthcd, and this prevents thecaller bcingcalled up by others during his conversation. By closing thecontact 17 the circuit T ,-716--17- Rot Batt-T is established and thelinesearcher is started; the reference Rot associated with anidentifying letter, for example, Rot indicates the magnet which conetrols the rotation of the element with the corresponding capitalreference letter, as C, Q, E, and G." By closing the contact 9, thecallers contact 11 in the collector of the linesearcher C is switchedin.

Due to the action of the seracher-magnet Rot, the line-searcher startsrevolving and during its rotation a brush corresponding to a free trunkline comes into contact with it, thereby closing the circuit T --8-1Q11-]2-J) c-l3-l 6ll5----T,.

The magnet b is excited and tilts the pointer, thereby causing thelatter to switch the trunk line on to the line of the callingsubscriber.

The magnet -d-- now comes into action and attracts its multiplearmature. The circuit being as follows: T -a-- i-26-25- 2223-24b-T owingto the circuit T 5 -l 0ll12-b0l 314l1 5-T the contact 18 is closed andestablishes the circuit 'l,-- ',=l 1 --2$-l-----.22-2l--2(1 19 l8--9-liatt.*'l,,, the magnet --7i having been already excited by thecircuit from T to T,. The contact 18 closes also the circuit29---Batt.--'l,, oi the third wire. The magnet arinaturc a continues toremain at tractcd and the magnet 5Z- opens the contact 8, whereby the(an-rent no longer passes through ll and no other pointer can be stoppedby the same contact.

The contact 28 is closed and the magnet -cenergized owing to the circuitT,, further opensthe contact 14-, whereby all other trunk linescontrolled by the same registratorv can not come into action as long asthe registrator is working.

The contact 34 is closed and therewith the magnet controlling theregistrator is connected tothe subscribefsline across the circuit T 12336 3 lfl3att T Signaling of the first figme.The above operations beingcompleted by the fact of the calling subscriber lifting his apparatusfrom the hook, the caller begins to signalthe first figure. To thiseiiect the caller, by means of the well known Strowger dial or anysimilar device, causes a series of interruptions of the contact 2 andthe armature of the magnet f, which has been excited completed,thecontact 2 remains closed and consequently the armature of the magnetf remains attracted a sufficient time for the delayed-action magnet-gcoming into operation due to the circuit T,,-l0 38g39l3attT wherewiththe contact 41 is closed andthe registrator pointers switch. in thoselines wand;z in front of which the pointer has come to stillstand.

The circuit T 3l3O424l-t3%12 Rot Batt-T is established and due to theaction of the magnet Rot the selector corresponding to the calledhundred starts revolving. Also the circuit T .,-3130- 42-41-4l3- iilh-]3att'1 is established and the magnet h of the selector E attractsits armature and closes the selector contact 45. If the trunk lineleading to Zm51F253BattT is established and the magnets ZZ4a areenergized. The magnet -Z- tilts the pointer and connects the trunk linecoming away from the selector to the trunk line leading to the 2ndselector. The magnet m closes the con tact 55 and establishes thecircuit T Z 585'756-5l-BattT and this circuit excites the magnet Z. Themagnet -12- closes the contact 59 and establishes the circuit TBatt'596O LibT,, and the magnet Lib (the'magnets Lib being a releasingmagnet for registrator D), attracts its armature and due to the circuitT,,(2 6l'60Lib-59 keeps it attracted until the registrators pointer isbrought back to its rest position. 7 7

On the magnet Lib coming into action the contact 30 is opened and themagnets -cand e are denergized, while the magnet Z continues to beenergized by the circuit T -Z)-2ei23-29-2l20-IIl (third wire)57--5G54l-Batt'il Accordingly the registrator D of the firstlinesearcher is released and left available for a new caller, while theconnection of the calling subscriber and first trunk line with theselector still remains subsisting.

Further the magnet m closes the contact 63 and thus establishes thecircuit T ,Batt-63-mot-G4;l28-Batt-T The magnet mremains energized a1-though the magnet itopens the contact 51, so that no other linecontrolled by the same registrator F is stopped until the lattersoperation is completed.

The magnet 2nfurther closes the con tact 73, whereby it connects up withthe caller the magnet p, controlling the registrator F, across thecircuit T -1-2-3 3G-II73 )-l3attT All this is cleiiected owing to thebrief pause following the signaling of the first figure.

Signaling of the Zest two figurca-The caller proceeds to signal the lastbut one ligure viz. the tens figure. The magnet 71, which was energizedby the last named cir cuit, drops its armature at each interruption andsends a series of impulses in the circuit T -6569-Rot -7l-72Bate-T andthe tens-pointer in the registrator l advances by a step at eachimpulse.

hen the signaling of the tens is completed the armature of the magnetpremains attracted a sufiicient time for the delayed action magnet q tocome into operation and to open the contact 70, whereby the rotationmagnet Rot of the tens is shut out and the contact 79 closed.

The signaling of the last or unit ligure causes the rotation magnet Rotto actuate the unit-pointer across the circuit T,,,G5- l:ot 7 97172-BattT and the unit-pointer advances by a step at each inipulse.

When the signaling of the unit-figure is completed, the armature of thecontrolling magnet 29 remains attracted and the contact 7% closed, thussetting into operation the delayed-action magnet r across the circuit TT27-lr-S3-T lhe circuit T -8l11ot T is energized whereby, j.

owing to the action of the rotation magnet Rot the connector G startsrevolving and the brushes thereof slide on its collector. hen the brushcorresponding to the energized trunk line comes opposite the called upsubscriber, different cases may present themselves.

The subscriber called up is free.-Under this condition the contact 94 ofthe connector, to which the fourth subscriber-wire leads, is not earthedsince the contact 92 in the corresponding group N is open. When thebrush comes opposite the called sub- 89-'a--90Batt---T is establishedacross the three winding magnet -t"-.

The magnet ---s--- then attracts the pointer of the connector andeonnectsup the line of the called subscriber to the trunk line comingfrom the selector The magnet --t-- attracts its armature and closes thecontact 96, wherewith the third wire at the called subscribers as wellas at the calling subscribers end is earthed across the contacts 96 and9-7, the magnet Af being excited by the second wire of the calledsubscriber across the connection T,--1-2--3-36-II-109 --A 11e- Batt-T26The magnet -u-- closes the contact 123 and energizes the releasingmagnets across Since the releasing magnets have opened the contacts 64,the magnets mand -n drop their armatures and the registrator F is setfree and made available for a new subscriber as soon as it has reachedits rest position.

By the closing of contact 96 on magnet -tthe circuit T24-97-96t57--III--20--21-25-26(La T is established, on which are. branched the circuits22-23- 24-b-T7 and 57-58-Z-T18, and the magnets a--d-b-Z- of the callingsubscriber continue to attract their armatures, whereby it is preventedthat the called subscriber on liftlng his receiver from the hook shouldstart into action the line-searcher to which he is connected. To thesaid circuit is connected in shunt the magnet --s--, which accordinglycontinues to maintain the connection with thecalled line.

The two third wire windings on the magnet -t are so designed that whenthey are in parallel the armature of the magnet t-- is. attracted, andwhen they are set in series.

inthe same circuit they oppose one another and the armature drops.

At the called subscribers end the resistance of the ringing apparatus issuch that the magnet B, cannot operate as lOIlg as the ringing apparatusis inserted in the circuit.

In this condition, the contact 101 being closed, the magnets ,--eistraversed by an interrupted current and consequently closes the contact103 at intervals and sends an intermittent current into the ringingapparatus of the called subscriber across the circuit: Corr. Alt(alternating current) 103- 104.-105-Bell106--107-108-T25.

When the called subscriber unhooks his receiver he thereby closes thecircuit T25- Batt -l12- B -113--110.99104=130 Microphone 107108--T25.The magnet B, is energized and closes the contact 122; the magnet --t istraversed by currents in opposite directions and lets its armature drop;the third wires are fed across the contacts 121-122- and the speakingline is tied at the callers end across the earth T1 and at the calledsubscribers end across the earth T25, the speaking connection being thuscompleted.

End of the conversation; disconnect ion. The disconnection is effectedwhen one of the two subscribers hangs up his receiver. The magnet A orthe magnet l3 are then deenergized, the third wires are interrupted, andthe magnets bhs actuating the swinging pointers also become deenergized.At the end of the line where the subscriber has hung up his receiver(for instance the called subscriber) also his magnets -a and -(Z-- aredeenergized. At the end of the calling line, where it has not yet beenhung up, only the magnet -a-- is cleanergized; the magnet -dremainsexcited across the circuit T 5-d--132-131 3 2-Micr--1--T1, and theengaged signal is sent over to the other subscriber. The same applies ifthe caller has hung up his receiver first.

Called subscriber engaged; disconnectz'0n.1f the called up telephone isengaged, the contact 94 of the called subscribers fourth wire is earthedand the circuit T23- 91--92-93--94c-95--89-u-90-Batt- T20 isestablished; the magnet -vis energized, op ns the contact 88 andprevents the magnet --t from coming into action. Meanwhile the magnet--u-- releases the. registrator, and the magnets -mand -n-- are de'cnergized. The third wire is therefore interrupted at the end of thecalling subscriber, who receives the engaged signal; in the same way asalready described also the magnet --e-- is deenergized since the contact101 has been opened.

In a 10,000 subscriber system, in lieu of the connector G a furtherselector is used which is connected up to the connector by means of athird registrator.

The registrators might also be operated electrically instead ofmechanically.

Of course the particulars regarding the form and constructional detailscan be varied from those described and illustrated without departingfrom the spirit and scope oi? the invention.

Having thus described our invention and how the same is to be carriedinto practice, what we desire to protect by Letters Patent 1. In anautomatic telephone system, linesearchers adapted to connect the callersline to a calling line, automatically, upon istrator is renderedinoperative and a secondary registrator isinserted, the secondaryregistrator being thereafter operable to actuate the second selectorsimilarly to the actuation of the first selector by the firstregistrator or to select in the connector a point corresponding to thecalled line and to connect the first trunk line that is served by thecallerssecondary registrator with the called llne, the secondaryregistratorbelng set free aupon the making of said connection, and agroupof magnets for each trunk leading to the connector, said magnetsbeing operable to maintain the connection of the calling line with thecalled line and to break the connection it the called line is occupied.

2. A searching device for automatic telephone systems comprising a setof springs and contacts arranged on the generating lines of a cylinder,a set of contacts to which each subscribers line leads, a set of loosepointers arranged at the level of a rowof contacts ofsaid set andrendered operative to rotate by expansion elements arranged on aspindle, brushes, equal in number to the pointers, secured to thespindle and bearing on the contacts of the controlling lines, and

electro-magnets operative to disengage the expansion elements from thepointers.

3. In a telephone system such as recited in claim 1, connectlonregistrators connected 7 to the trunk lines in shunt and to the callinglines successively.

4. In a telephone system such as recited in claim 1, magnets effectingthe release of the elements recited as soon as either the hook on thecalling instrument or the instrument on thecalled instrument ishung up.

5. An automatic telephone system comprising line searchers having thecalling lines connected to multiple horizontal circular rows ofcontacts, a number of pointers revolving in front'oi' said circular rowsof contacts and being the extremities of as many trunk lines as thenumber of the pointers, means to stop the. revolution of each pointerindependently of the others; registrators associated with the trunklines and rendered operative when the calling line forms the firstfigure of the number of the called line, means for starting a firstselector when the registrator comes to a standstill and determining onthis selector a group for a stop; first selectors oi the sameconstruction as the line searchers and having contact springs formingthe extremities of a second set of trunk lines arranged in groups, eachgroup comprising the trunk lines corresponding to a determined group offurther selectors, the pointers of the first selectors being theextremities of the trunk lines from the line searchers; furtherselectors with registrators; a final set of registrators to distinctlyrecord the tens and units figures of the called line number; a connectorof the same construction as the line searcher, its pointers being theextremities of trunk lines, and the spring contacts on its stationaryframe being the extremities of subscribers lines to be called, andhaving means whereby its registrator establishes for each pointer duringits rotation a group where it can stop and ten positions of rest in saidgroup; sets of relays to control the operations, and relays at theconnectors to perform the calling of the desired subscriber as soon asthe connectors pointer has stopped on the terminal of the called line,to disengage and free the intermediate members as soon as either of thesubscribers hangs up the telephone as well as when the revolvingconnector-s pointer finds that the called line is engaged.

(3. An automatic telephone system comprising line searchers consistingof several sets of contacts horizontally arranged in circular rows, therows being vertically super- }mscd so as to form a cylinder, thecontacts on the same generatrix being multiplying contacts of a line, acentral rotatable spindle, a number of pointers on said spindle, andmeans for having the pointers driven by the spindle independently, meansfor disengaging each rotating pointer from the spindle as soon as itconnects a calling line, and brushes cooperating with a circular set ofcontacts and rotating with the spindle.

In testimony whereof we hereunto aifix our signatures in the presence oftwo witnesses.

Inc. GIUSEPPE SIMONETTA. ING. AUGUSTO ROSA. lVitnesses OTTORINO HARRARI,IVAN LAVRETSKY.

